Thank you for uploading it to dropbox, something is wrong with the uploader here – I will look into that. I’ve installed the theme with all the plugins but the search still works for me.
However I just released the 3.1 version of the plugin 2 days ago. It has a few changes here and there, please download it from codecanyon, delete the old one, and install the new one. There is a chance that it will help.
Sometimes it solves client side issues.
If you like my products, don't forget to rate them on codecanyon :)